• use warnings;
• use strict;

When I ran your script with use warnings;:

Reference found where even-sized list expected at ./junk.pl line 6.
Use of uninitialized value $amount in addition (+) at ./junk.pl line 2
+7.
Use of uninitialized value $total_admin_expenses in addition (+) at ./
+junk.pl line 27.
Use of uninitialized value $_[0] in reverse at ./junk.pl line 35.
[download]

It appears to me that the best solution is to declare the variables with our. Is there any way to do this without writing our for each variable or without listing all of the variable names within an our declaration and again when I assign values to them?

Since I am only writing a report with Perl, I don't have a lot of stuff competing for the namespace. I would like to keep the readability high and the amount of redundancy low so that the code is easy to change and easy to read. If I package this into an object with getters and setter later then I can find and replace our with my, but for now I think that our seems to be the best choice. Thoughts?

use strict;
# while I would like to do this:
#
# our
# (
# $x = 1;
# $y = 2;
# );
#
# it seems that I must do:

use ($x, $y);
$x = 1;
$y = 2;

# or this:

our $x = 3;
our $y = 4;

# before I can do:

$x = 5;
$y = 6;
[download]

should I do the following instead?

use strict;
no strict "vars";
$x = 5;
$y = 6;
[download]

Thank you,

Is there any way to do this without writing our for each variable or without listing all of the variable names within an our declaration and again when I assign values to them?

Sure

my( $foo, $bar ) = ( 1, 2 );
[download]

should I do the following instead?

No, that misses the point , might as well not use strict at all in that case.  strict itself confers no benefits; The benefits come from avoidance of the bad practices forbidden by  strict :)

To understand these read: See Tutorials: Variable Scoping in Perl: the basics, Coping with Scoping , Mini-Tutorial: Perl's Memory Management, Lexical scoping like a fox, Read this if you want to cut your development time in half!

The free Modern Perl book covers all this too

With very short scripts (less than 6 lines, say), it probably confers no benefits.

For anything longer, use strict qw(subs vars) seems to always be appropriate. use strict qw(refs) is usually appropriate, but it's sometimes useful to allow non-strict refs.

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

Is there any way to set my as the default scope for variables when no scope is specified? Why isn't this the case now?

Thanks,

That is the unexpected result that I gaet from the following code. Why is it making a hash?

Because this is what you wrote

my $hashref = {};
my %hash = $hashref;
[download]

$ perl -MData::Dump -e " dd { {} } "
{ "HASH(0x3f8a6c)" => undef }
[download]

Say it with me:

my $hashref = { 'hashes', 'are', 'curly', 'ones' };

my $arrayref = [ 'arrays', 'are', 'square' ];

my %hash = ( 'lists are round' , 'hashes want pairs');

I highly recommend perlintro, http://learn.perl.org/books/beginning-perl/, http://perl-tutorial.org/, Modern Perl , Tutorials: Basic debugging checklist , brian's Guide to Solving Any Perl Problem

Here's another way to comma'ify your numbers that avoids the two reversees by using substr, pos and look-around assertions in the regex.

knoppix@Microknoppix:~$ perl -E '
> sub add_commas
> {
>     my $number = shift;
>     substr $number, pos $number, 0, q{,}
>        while $number =~ m{ (?<= \d ) (?= \d{3} (?: , | \z ) ) }xg;
>     return $number;
> }
> 
> say add_commas( $_ ) for qw{
>    1
>    12
>    123
>    1234
>    12345
>    123456
>    1234567
>    12345678
>    123456789
>    1234567890
>    };'
1
12
123
1,234
12,345
123,456
1,234,567
12,345,678
123,456,789
1,234,567,890
knoppix@Microknoppix:~$
[download]

I hope this is of interest.